1. Field of the Invention
The present invention relates to a nano-carrier, a complex of an anticancer drug and a nano-carrier, a pharmaceutical composition thereof, a method for manufacturing the complex, and a method for treating a cancer by using the pharmaceutical composition and, more particularly, to a nano-carrier which is able to carry an anticancer drug and release the anticancer drug near the location of cancer cells, a complex of an anticancer drug and a nano-carrier, a pharmaceutical composition thereof, a method for manufacturing the complex, and a method for treating a cancer by using the pharmaceutical composition
2. Description of Related Art
Chemotherapeutic agents are cytotoxic drugs that usually target fast growing cells through blockage of critical pathways for cell division as well as promoting apoptosis. One kind of the widely used chemotherapeutic agents serving as anti-virus and/or anti-cancer drugs is nucleotide-like compounds. The nucleotide-like compounds can kill the virus-infected cells and/or cancer cells or inhibit the growth thereof through interfering with the nucleic acid metabolisms and cell divisions, and promoting apoptosis. However, the nucleotide-like compounds are also cytotoxic to normal cells, so some side effects and complications may occur during the administration of these compounds, and the dosages thereof must be limited. Also, some nucleotide-like compounds may interfere with the gene replication and transcription in mitochondrions and cell nucleuses when these compounds are administered over a long period of time. Hence, some side effects, such as mitochondrial disorder and bone marrow suppression, may occur in the patients taking these compounds for a long time.
In the clinical researches, it is found that when the nucleotide-like compounds are used in the anti-virus therapy, drug-resistant strains of virus may exist in some patients taking drugs with a single-agent for a long time. Hence, the activity of the virus in serum increases again, the patient's condition gets worse, and the drugs have to be replaced by a new agent. In addition, when the nucleotide-like compounds used as an anti-cancer drug are administered for a long time, cancer cells with drug-resistant strains may be generated and cause the efficacy of the chemical therapy to decrease. Furthermore, the nucleotide-like compounds attack both normal and cancerous cells thereby often resulting in significant side effects, notably lethal cardiac toxicity. Hence, the dose of the anti-cancer drug must be limited to prevent side effects.
Fluorouracil (5-FU) is one kind of nucleotide-like compounds, which is the main ingredient for treating GI tract cancers, including colorectal, stomach, and oral cancers in the past decades. 5-FU is a pyrimidine analogue and can be converted in the cancer cell to form cytotoxicity metabolites, which then become incorporated into DNA and RNA. The compounds eventually induce cell cycle arrest and apoptosis by inhibiting DNA synthesis.
Therefore, it is desirable to provide an anti-cancer drug, and the drug release strategies thereof can be controlled and sustained to increase local concentration of anti-cancer drugs, in order to decrease potential side effects.